A Backbone.js collection class with utility methods for iterating and picking

IterableCollection.js

IterableCollection = Backbone.Collection.extend({
    initialize: function() {
        //_.bindAll(this, )
        this._resetIndexes();
    },
    _resetIndexes: function() {
        this.currentIndex = 0;
        this.hasSelection = false;
    },
    parse: function(response) {
        return response.objects;
    },
    current: function() {
        if (this.length < 1) return false;
        return this.at(this.currentIndex);
    },
    hasPrev: function () {
        if (this.length < 2) return false; 
        return this.at(this.currentIndex-1) != undefined;
    },
    hasNext: function() {
        if (this.length < 2) return false; 
        return this.at(this.currentIndex+1) != undefined;
    },
    prev: function() {
        if (this.hasPrev()) {
            this.currentIndex--;
            this.trigger('index:current:set');
            return this.current();
        };
        return false;
    },
    next: function() {
        if (this.hasNext()) {
            this.currentIndex++;
            this.trigger('index:current:set');
            return this.current();
        };
        return false;
    },
    restart: function() {
        this._resetIndexes();
        this.trigger('index:restart');
        this.trigger('index:current:set');
        this.trigger('selection:restart');
        this.trigger('selection:unset');
    },
    prevRound: function() {
        if (this.hasPrev()) {
            this.currentIndex--;
        } else {
            this.currentIndex = this.length-1;
        };
        this.trigger('index:current:set');
        return this.current();
    },
    nextRound: function() {
        if (this.hasNext()) {
            this.currentIndex++;
        } else {
            this.currentIndex = 0;
        };
        this.trigger('index:current:set');
        return this.current();
    },
    
    seek: function(index) {
        this.hasSelection = true;
        this.currentIndex = index;
        this.trigger('selection');
        this.trigger('selection:set');
        this.trigger('index:current:set');
        return this.current();
    },
    seekModel: function(model) {
        index = this.indexOf(model);
        return this.seek(index);
    }
});